A GR.7 Harrier prepares for take-off from HMS Illustrious.
Harrier GR.7s, Sea Harrier FA.2s and Sea King HAS.6s aboard HMS Invincible.
The integrated bridge system.
The large aircraft hangar deck on the Invincible class aircraft carrier.
HMS Invincible with extended flight deck.
HMS Invincible on sea trials in February 2003, following refit.
HMS Invincible arriving for refit at Babcock's Rosyth yard.
Ark Royal, with the Merlin HM.1 helicopter on deck, heading out to start sea trials on completion of refit at Rosyth in November 2001.
HMS Illustrious sails into Rosyth Dockyard for the start of refit in October 2002. HMS Invincible can be seen in the background.
HMS Invincible sailing past the city of Edinburgh.
HMS Invincible seen at Babcock Rosyth in the foreground. Ark Royal is at the top of the picture.

HMS Ark Royal Invincible class aircraft carrier

The first-of-class HMS Invincible aircraft carrier was built by Vickers Shipbuilding and Engineering (now BAE Systems Marine) at Barrow-in-Furness. The ship was commissioned in July 1980. The two sister ships HMS Illustrious and HMS Ark Royal, both built at the Swan Hunter Shipbuilders yard in Wallsend, were commissioned in 1982 and 1985.

Since the end of the Cold War, the primary role of the 20,600t aircraft carriers changed from sea control to maritime force projection, to include maritime strike, littoral manoeuvres and command and control of land operations.

"The Invincible Class aircraft carriers accommodate over 1,000 crew including 350 air crew and 80 officers."

Decommissing HMS Illustrious, HMS Ark Royal, HMS Invincible

HMS Invincible was decommissioned in August 2005. However, she remained on the Naval Reserve List to be deployed if required and was not withdrawn from service until 2010.

HMS Ark Royal was to be retired in 2016, however this was moved forward under the 2010 Strategic Defence and Security Review and she was decomissioned in March 2011.

HMS Illustrious currently operates as a helicopter carrier and is due to be decommisioned in 2014.

The Invincible class will be replaced as the British Navy’s aircraft carriers by the Queen Elizabeth class. The first two carriers, HMS Queen Elizabeth and HMS Prince of Wales are due to enter service in 2016 and 2018.

Invincible class carrier armaments

The vessels were armed with a Sea Dart twin launcher, installed on the forecastle of the ship near the ski ramp. However, the missile system was removed from all three carriers and the flight deck extended, to provide more capacity for aircraft and enable take-off for RAF Harrier GR.7/9 aircraft. HMS Invincible completed a refit in March 2003. Illustrious completed refit at Babcock’s Rosyth yard in November 2004.

In March / April 2003, HMS Ark Royal was deployed as part of the UK task force in support of Operation Iraqi Freedom. On board were Merlin HMA1 and Sea King ASaC mk7 helicopters, the first operational deployment of these aircraft.

HMS Ark Royal refit

Ark Royal completed a refit in September 2006 which included the fitting of better aviation facilities, an enhanced communications mast, SCOT 5 satellite communications system, Bowman command and control communications system, electronic charting and towed sonar decoy system. The refit allowed the vessel to take on additional commando and helicopter carrier roles as well as maritime strike, and command and control platform.

Ark Royal could now carry up to 400 troops and RAF Chinook helicopters, as well as Army Apaches and Navy Sea King and Merlin helicopters. Ark Royal officially rejoined the fleet in December 2006 and began a two-month period of sea training in January 2007 before returning to active service.

Command systems

The combat data system was BAE Systems ADIMP with communication links link 10, link 11 and link 14. Following refit, HMS Invincible had the combat system upgraded to the same standard as Illustrious and Ark Royal, with multi-function consoles and flat-panel colour displays. The secure satellite communications system, the Astrium (formerly Matra Marconi) SCOT, had the capacity to handle data rates up to 2Mb/s.


HMS Ark Royal was armed with three mk15 Phalanx close-in weapon systems (CIWS) from Raytheon and General Dynamics. Each Phalanx CIWS had one 20mm M61A1 Vulcan Gatling-principle gun which fired 3,000 rounds a minute to a range of 1.5km.

"The Invincible aircraft carriers were originally armed with a Sea Dart twin launcher."

HMS Invincible and Illustrious each had three Thales Nederland (formerly Signaal) Goalkeeper CIWS. Goalkeeper’s Gatling principle 30mm gun provided a maximum firing rate of 4,200 rounds a minute with a range of 1,500m.

All three carriers were also equipped with two GAM-B01 20mm guns from Oerlikon-Contraves and BAE Systems, which have a maximum range of 2km and firing rate of 1,000 rounds a minute.


The Invincible Class was fitted with the Thales Defence Type 675(2) jamming system and a UAT(8) electronic support measures system also supplied by Thales Defence (formerly Racal).

The ship’s decoy system was the Royal Navy’s Outfit DLJ with Sea Gnat. There are eight 130mm six-barrel launchers produced by Hunting Engineering. Chemring and Pains Wessex produce the Sea Gnat chaff and infra-red decoys.


The tailored air group (TAG) comprised up to 24 aircraft including up to nine combined RAF/RN Joint Force Harrier GR7/GR9 aircraft. The Royal Navy FA2 Sea Harrier aircraft were progressively withdrawn from service from March 2004 and the last squadron was decommissioned in March 2006.

The TAG also included a mix of helicopters, depending on role: Sea King ASaC mk7 airborne early warning helicopters, Sea King and Chinook support helicopters and Merlin HM.1 anti-submarine helicopters.

The Invincible runway is about 170m long with a ski ramp set at 12°. In the hangar deck the aircraft are tethered to the floor using securing chains with tension clamps. Selex Sensors & Airborne Systems (formerly Galileo Avionica) was contracted to supply the SPN-720 precision approach radar for the landing of Harrier GR9 aircraft on Ark Royal and Illustrious in February 2005. The radar system, with a new TACAN (tactical air navigation) system, entered service on the vessels in April 2008.


The BAE Systems Type 909 G/H-band fire control radar, which provided target tracking and illumination for the Sea Dart missile, has been removed from the three carriers. BAE Systems type 996 surface search radar antennae is mounted very high on the tower between the two funnels. HMS Ark Royal has Type 992.

"Since the end of the Cold War, the primary role of the 20,600t aircraft carriers has changed from sea control to maritime force projection."

Both radars operate at E and F bands. BAE Systems type 1022 air search radar operates at D band. HMS Invincible and Ark Royal were equipped with Kelvin Hughes type 1006 navigation radar and HMS Illustrious had type 1007, both operating at I band.

Qinetiq, with Babcock Design & Technology, were awarded a contract to provide an advanced technology mast communications and radar mast for HMS Ark Royal. The sensors and antennas are housed within the structure, protected from the environment.

The sonar system was the hull-mounted Type 2016 active / passive search and attack sonar by Thales Underwater Systems (formerly Thomson Marconi Sonar).


The Invincible class carriers were powered by COGAG (combined gas turbine and gas turbine), consisting of four Rolls-Royce Olympus TM3B gas turbine engines generating 97,000hp, providing a speed of 28kt. At the economical speed of 19kt the range was 7,000 miles.